Fix wrong indentation in vppctl script

Change-Id: I6c67df0cef53f93161e3d6b697c4d0fdc1fee8a7
Signed-off-by: Andrew Li <zhaoxili@cisco.com>
diff --git a/vpp-api-test/scripts/vppctl b/vpp-api-test/scripts/vppctl
index 58a0292..4fdf03c 100755
--- a/vpp-api-test/scripts/vppctl
+++ b/vpp-api-test/scripts/vppctl
@@ -108,7 +108,7 @@
                                 sys.stdout.write('\n')
                 else:
                         try:
-                        prompt.cmdloop()
+                                prompt.cmdloop()
                         except KeyboardInterrupt:
                                 sys.stdout.write('\n')
         else: